Hi Nigel,
Be aware that these transports are simply the very worst I have ever seen (a big thanks to Philips). Total failure rates with brand new transports sent from Cyrus was about 50%. No joke, these ones didn't read period. Cyrus was one that got the highest quality parts. Now, this doesn't count the transports that performed very poorly. They played a CD, not well and would fail sooner than later.
We got entire CDM transports, we didn't play with heads or motors as they were not available in pieces.
This is really sad, because Cyrus makes excellent products. They relied on Philips for the transports as they had for years, and many other manufacturers. So all I will say to you is to consider this. If you are not a tech really use to working on CD players and can tell a good transport from a bad one, either take your machine to a good tech, or replace it. Your good tech may refuse to work on it, and if he does it is because he knows it may take several replacements before finding a okay one (notice I didn't say good). A tech with poor ethics will slap the new one in and give it back to you as long as it works. A bad tech doesn't even know to check. The test points are not documented or marked. Experience is key here.
-Chris